Joint aspiration and injection and synovial fluid analysis

The Diagnostic and Prognostic Value of Synovial Fluid Analysis in Joint Diseases

Liquid biopsy is an emergent test method for the diagnosis and prognosis in the clinic. Joint fluid, also known as synovial fluid, contains a variety of bioactive constituents that can be selectively detected and further evaluated in a convenient fashion. Therefore, synovial fluid analysis functions as a specific form of liquid biopsy and plays a vital role in numerous joint diseases. In spite of the component analysis of aspirated synovial fluid beingconsidered as the gold standard for diagnosis of joint infections, biopsy of joint fluid benefits the initial diagnosis and long-term prognosis of degenerative, inflammatory, autoimmune, traumatic, congenital, and even neoplastic joint diseases. The convenience and accuracy for disease evaluation are significantly elevated as a result of the combination of synovial fluid analysis and other novel clinical technologies. In this review, we shed light on the latent role of synovial fluid in the diagnosis and prognosis of articular diseases and proposed future prospects for relevant research in this field.

[Sterile puncture of large joints]

OBJECTIVE

Puncture of large joints is performed for diagnostic purposes on the one hand and for the treatment of joint pathologies on the other. Puncture can be used for rapid pain relief by relieving effusions or intra-articular hematomas. The obtained puncture specimen allows immediate visual assessment and subsequent microscopic-cytological and microbiological evaluation in the laboratory.

INDICATIONS

The indication for puncture of a large joint is for diagnosis and/or therapy of inflammatory, traumatic or postoperative joint problems. Diagnostic punctures are used to obtain punctate, to differentiate the location of pain or (rarely) to apply contrast medium for magnetic resonance arthrography. Therapeutic punctures allow the injection of drugs or platelet-rich plasma (PRP) as well as the relief or drainage of effusions.

CONTRAINDICATIONS

If there are inflammatory skin alterations-especially purulent inflammation-joint punctures through these lesions are absolutely contraindicated. Special attention is necessary if the patients are on anticoagulants.

SURGICAL TECHNIQUE

Absolute sterile handling is mandatory. Unnecessary pain can be avoided by a sterile skin wheal of local anesthesia, safe puncture points, and careful handling of the cannulas.

POSTOPERATIVE MANAGEMENT

Joint aspiration material has to be handled according to the local, intrahospital rules in a timely manner. Puncture sites are covered with sterile dressings, and if intra-articular medication is administered, the joints have to be passively moved through the range of motion to distribute the medication. Thereafter, compression therapy from distally to proximally while also covering the puncture site avoids recurrence of swelling or hematoma.

FACTS

If sterile conditions are guaranteed, infections rarely occur (0.04-0.08%, 4-8/10,000 cases). The risk of false-positive detection of microorganisms is extremely low.

Intra-articular injection in the hind limb joints of dromedary camels (Camelus dromedarius) using anatomical and arthrographic-guided landmarks

Background and Aim:

A healthy joint is an important structure for the proper movement of the camel limb. Intra-articular (IA) injection is frequently used in veterinary practice for diagnostic and therapeutic purposes of joint injuries. Thus, the current study aimed to describe the injection of the hindlimb joints in dromedary camels based on the anatomical and arthrographic-guided landmarks.

Materials and Methods:

Eighteen orthopedically sound adult camels (mean±standard deviation age: 78±12 months) of both sexes were included in this study. Three camels were euthanized to identify anatomical features in the hindlimb joints and related structures. IA injections were performed in the hindlimbs of 5 camel cadavers to evaluate the optimal IA injection site, which was confirmed by arthrography. The optimized IA injection technique was applied in 10 live camels and confirmed by arthrocentesis and arthrography. For each joint, injection criteria (number of attempts, difficulty of injection, and successful injection) were assessed, scored, and statistically compared to the other joints.

Results:

The summation of IA injection criteria scores was significantly higher (p<0.05) in the femorotibial, femoropatellar, tibiotarsal, fetlock, pastern, and coffin joints in comparison to the hip joint.

Conclusion:

Anatomical and arthrographic-guided techniques offer considerable advantages for the characterization of anatomical landmarks and selection of the appropriate IA injection site in the hindlimb in dromedary camels. Furthermore, a reference approach for camels was established that is different from the approach for cattle and horses.

Intra-articular injection techniques of the buffalo (Bubalus bubalis) hindlimb digit using anatomical and contrast arthrography-guided landmarks

This study was designed to evaluate and compare the optimal sites for intra-articular (IA) injection into the digits of buffalo by discrimination of the injection criteria. Forty-eight cadaveric hind digits of adult buffalos and nine live ones were assigned for three trial investigations. In the first division, eighteen sound cadaveric limbs were used to describe the anatomical features of the hind digit. In the second division, thirty cadaveric limbs (ten for each approach) were injected with an equal volume of iopamidol through relevant joint pouches to compare the dorsal, lateral and plantar IA approaches for each joint. The former technique was applied to nine live, healthy adult buffaloes to evaluate the accuracy of IA injection of the hind digit in vivo. Injection criteria were assessed, scored and statistically compared among the three approaches. The summation of injection criteria scores showed a significant increase (P < 0.05) in the dorsal and lateral approaches for IA injection of the fetlock, pastern and coffin joints in the buffalo digit compared to the plantar one. However, median and range of injection criteria scores between the dorsal and lateral approaches were slightly less significant. In conclusion, the present study established a reference for IA injection of the buffalo digit that could aid the diagnosis and treatment of digit-related lameness.

GEL-MAN Hydrogel Loaded With Triamcinolone Acetonide for the Treatment of Osteoarthritis

One of the major challenges for the treatment of osteoarthritis (OA) with therapeutic drugs is the short half-life of drugs in the joint cavity. The severity of OA often fluctuates with time and inflammatory factors. Here, we describe the use of a hydrogel material, named Gel-Man, to solve the problem of rapid release of drugs. Gel-Man could encapsulate a series of therapeutic drugs and be degraded by hydrogen peroxide. It could be decomposed, and release drugs controlled by the concentration of hydrogen peroxide in the arthritic joint cavity. This hydrogel loaded with triamcinolone acetonide (TA) could slowly release the drug upon exposure to hydrogen peroxide in the joint cavity in patients suffering from osteoarthritis. The combination of TA and GEL-MAN hydrogels can slowdown the progression of degenerative change of osteoarthritis by maximizing the therapeutic efficacy and prolong the duration of drug treatment.

Laboratory testing of extravascular body fluids: National recommendations on behalf of the Croatian Society of Medical Biochemistry and Laboratory Medicine. Part II - Synovial fluid

Joint diseases are conditions with an often progressive and generally painful nature affecting the patient's quality of life and, in some cases, requiring a prompt diagnosis in order to start the treatment urgently. Synovial fluid (SF) laboratory testing is an important part of a diagnostic evaluation of patients with joint diseases. Laboratory testing of SF can provide valuable information in establishing the diagnosis, be a part of a patient's follow-up and treatment with the purpose of improving the patient's health and quality of life. Synovial fluid laboratory testing is rarely performed in Croatian medical biochemistry laboratories. Consequently, procedures for SF laboratory testing are poorly harmonized. This document is the second in the series of recommendations prepared by the members of the Working group for extravascular body fluid samples of the Croatian Society of Medical Biochemistry and Laboratory Medicine. It addresses preanalytical, analytical, and postanalytical issues and the clinical significance of tests used in SF laboratory testing with the aim of improving the value of SF laboratory testing in the diagnosis of joint diseases and assisting in the achievement of national harmonization. It is intended for laboratory professionals and all medical personnel involved in synovial fluid collection and testing.

A Versatile, Low-Cost, Three-Dimensional-Printed Ultrasound Procedural Training Phantom of the Human Knee

The use of musculoskeletal ultrasound is expanding in many medical disciplines, and simulation trainers have been successfully employed to help practitioners learn various ultrasound techniques. While there are fewer commercial trainers in musculoskeletal ultrasound than other ultrasound modalities, the ones that do exist can be prohibitively expensive. Several less expensive phantom trainers have been described in the literature, including those made of ballistic gelatine. The authors present a three-dimensional printed knee phantom that was overlaid with ballistic gelatine as a viable option for training.

Toxicology Evaluation of Drugs Administered via Uncommon Routes: Intranasal, Intraocular, Intrathecal/Intraspinal, and Intra-Articular

As the need for nasal, ocular, spinal, and articular therapeutic compounds increases, toxicology assessments of drugs administered via these routes play an important role in human safety. This symposium outlined the local and systemic evaluation to support safety during the development of these drugs in nonclinical models with some case studies. Discussions included selection of appropriate species for the intended route; conducting nonclinical studies that closely mimic the intended use with adequate duration; functional assessment, if deemed necessary; evaluation of local tissues with special histological staining procedure; and evaluations of safety margins based on local and systemic toxicity.

Characteristics of particulate and non-particulate corticosteroids. Indications for their use in chronic pain treatments

Corticosteroids been used frequently in pain treatments since the middle of last century (1952). Due to a review of the complications as a result of their application in epidural injections, the United States of America Food and Drug Administration (FDA) issued an «alert controversy» requesting that a warning label should be added to injectable corticosteroids, where risks must be described (loss of sight, brain damage, paralysis and death) when administering by this route. It must be mentioned that there are different types of corticosteroids with diverse characteristics, which as a result, may produce different side-effects. Due to the aforementioned developments, the controversies that have arisen, and the lack of well-conducted studies on the use of steroids in epidural injections, we must begin by reviewing their indications in different pain conditions.

Effect of Asian dust on pulmonary function in adult asthma patients in western Japan: A panel study

BACKGROUND

Asian dust (AD) has become a major health concern. The concentration of AD is typically expressed in particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, PM10 and PM2.5 consist of various substances besides AD. Light detection and ranging (LIDAR) systems can selectively measure the quantity of AD particles to distinguish non-spherical airborne particles from spherical airborne particles. The objective of this study was to investigate the relationship between pulmonary function in adult asthma patients and AD using LIDAR data.

METHODS

Subjects were 231 adult asthma patients who had their morning peak expiratory flow (PEF) measured from March to May 2012. A linear mixed model was used to estimate the association of PEF with sand dust particles detected by LIDAR.

RESULTS

Increases in the interquartile range of AD particles (0.018 km(-1)) led to changes in PEF of -0.42 L/min (95% confidence interval [CI], -0.85 to 0.01). An increase of 11.8 μg/m(3) in suspended particulate matter and 6.9 μg/m(3) in PM2.5 led to decreases of -0.17 L/min (-0.53 to 0.21) and 0.03 L/min (-0.35 to 0.42), respectively. A heavy AD day was defined as a day with a level of AD particles >0.032 km(-1), which was the average plus one standard deviation during the study period, and six heavy AD days were identified. Change in PEF after a heavy AD day was -0.97 L/min (-1.90 to -0.04).

CONCLUSIONS

Heavy exposure to AD particles was significantly associated with decreased pulmonary function in adult asthma patients.

Anterolateral Portal Is Less Painful than Superolateral Portal in Knee Intra-Articular Injection

Purpose

Intra-articular knee injections are commonly performed in clinical practice for treating various knee joint disorders such as osteoarthritis and rheumatoid arthritis. When selecting the portal for injection, not only intra-articular needle accuracy but also procedural pain should be taken into consideration. The purpose of this study was to determine whether injection through anterolateral portal provokes less pain and provides better pain relief compared to superolateral portal.

Materials and Methods

A total of 60 patients with primary osteoarthritis of the knee receiving intra-articular injections were randomized into 2 groups according to the type of portal approach; anterolateral or superolateral. All patients received hyaluronic acid (20 mg) and triamcinolone (40 mg) as the first injection followed by second and third injections of hyaluronic acid on a weekly basis. Underlying knee pain, procedural pain, and knee pain at 4 weeks were evaluated using visual analogue scale (VAS).

Results

Injection through anterolateral portal provoked less pain (VAS, 1.5±1.3) than the superolateral portal (VAS, 1.5 vs. 2.7; p=0.004). No differences were found in the degree of pain relief at weeks between the two groups (p=0.517).

Conclusions

We recommend the use of anterolateral portal for intra-articular knee injection as it provokes less pain and comparably short-term pain relief than the superolateral portal.

Where and how to inject the knee--a systematic review

Objectives

The knee can be injected at different anatomic sites with or without image-guidance. We undertook a systematic review to determine the accuracy of intra-articular knee injection (IAKI) and whether this varied by site, use of image-guidance, and experience of injectors, and whether accuracy of injection, site, or use of image-guidance influenced outcomes following IAKIs.

Methods

Medline, Embase, AMED, CINAHL, Web of Knowledge, Cochrane Central Registers for Controlled Trials up to Dec 2012 were searched for studies that evaluated either accuracy of IAKIs or outcomes related to accuracy, knee injection sites, or use of image-guidance. Within-study and between-study analyses were performed.

Results

Data from 23 publications were included. Within-study analyses suggested IAKIs at the superomedial patellar, medial midpatellar (MMP), superolateral patellar (SLP) and lateral suprapatellar bursae sites were more accurate when using image-guidance than when blinded (ranges of pooled risk difference 0.09–0.19). Pooling data across studies suggested blinded IAKIs at the SLP site were most accurate (87%) while MMP (64%) and anterolateral joint line (ALJL) sites were (70%) least accurate. Overall about one in five blinded IAKIs were inaccurate. There was some evidence that experience of the injector was linked with improved accuracy for blinded though not image-guided injections. Based on a small number of studies, short but not longer-term outcomes for ultrasound-guided were found to be superior to blinded IAKIs.

Conclusions

Image-guided IAKIs are modestly more accurate than blinded IAKIs especially at the MMP and ALJL sites. Blinded injections at SLP site had good accuracy especially if performed by experienced injectors. Further studies are required to address the question whether accurate localization is linked with an improved response.

Optimizing current treatment of gout

Gout is the most common inflammatory arthritis worldwide. Although effective treatments exist to eliminate sodium urate crystals and to 'cure' the disease, the management of gout is often suboptimal. This article reviews available treatments, recommended best practice and barriers to effective care, and how these barriers might be overcome. To optimize the management of gout, health professionals need to know not only how to treat acute attacks but also how to up-titrate urate-lowering therapy against a specific target level of serum uric acid that is below the saturation point for crystal formation. Current perspectives are changing towards much earlier use of urate-lowering therapy, even at the time of first diagnosis of gout. Holistic assessment and patient education are essential to address patient-specific risk factors and ensuring adherence to individualized therapy. Shared decision-making between a fully informed patient and practitioner greatly increases the likelihood of curing gout.

Current perspectives in stem cell research for knee cartilage repair

Protocols based on the delivery of stem cells are currently applied in patients, showing encouraging results for the treatment of articular cartilage lesions (focal defects, osteoarthritis). Yet, restoration of a fully functional cartilage surface (native structural organization and mechanical functions) especially in the knee joint has not been reported to date, showing the need for improved designs of clinical trials. Various sources of progenitor cells are now available, originating from adult tissues but also from embryonic or reprogrammed tissues, most of which have already been evaluated for their chondrogenic potential in culture and for their reparative properties in vivo upon implantation in relevant animal models of cartilage lesions. Nevertheless, particular attention will be needed regarding their safe clinical use and their potential to form a cartilaginous repair tissue of proper quality and functionality in the patient. Possible improvements may reside in the use of biological supplements in accordance with regulations, while some challenges remain in establishing standardized, effective procedures in the clinics.

Effectiveness of aspiration in knee joint effusion management: a prospective randomized controlled study

PURPOSE

Knee effusion is a common symptom in various knee disorders of both traumatic and non-traumatic aetiology. Although intra-articular aspiration is a widespread treatment approach, its beneficial effect has not been confirmed by a randomized controlled study. The purpose was to evaluate the effectiveness and safety of joint aspiration in acute knee effusion, in relation to traumatic or non-traumatic aetiology.

METHODS

One hundred and sixty-seven consecutive patients with acute knee joint effusion were allocated in a randomized controlled fashion into two groups. In the first group, joint aspiration was performed, while in the second group, no aspiration was performed. Range of motion, pain relief, use of analgesics and oedema were evaluated post management. The Knee Society Score and the International Knee Documentation Committee Subjective Evaluation Form were also obtained. In addition, a subgroup analysis of our results in relation to the presence of trauma or not was performed.

RESULTS

Aspiration exhibited a temporary improvement in all clinical parameters evaluated, especially in the post-traumatic effusion. However, this improvement lasted only for the first week, due to the early re-accumulation of the effusion. There was no difference between the different groups regarding the clinical outcome in neither trauma or non-trauma patients at the end of the follow-up period. Aspiration aided in earlier establishment of the diagnosis in the non-trauma cases of effusion.

CONCLUSIONS

Aspiration resulted in only temporary improvement of the outcome in the treatment of traumatic or not traumatic knee effusion. Aspiration is suggested in effusions of unknown origin in order to establish the diagnosis and for immediate clinical relief. However, aspiration should be performed with consideration in the presence of trauma.

Biocompatibility and enhanced osteogenic differentiation of human mesenchymal stem cells in response to surface engineered poly(D,L-lactic-co-glycolic acid) microparticles

Tissue engineering strategies can be applied to enhancing osseous integration of soft tissue grafts during ligament reconstruction. Ligament rupture results in a hemarthrosis, an acute intra-articular bleed rich in osteogenic human mesenchymal stem cells (hMSCs). With the aim of identifying an appropriate biomaterial with which to combine hemarthrosis fluid-derived hMSCs (HF-hMSCs) for therapeutic application, this work has investigated the biocompatibility of microparticles manufactured from two forms of poly(D,L-lactic-co-glycolic acid) (PLGA), one synthesized with equal monomeric ratios of lactic acid to glycolic acid (PLGA 50:50) and the other with a higher proportion of lactic acid (PLGA 85:15) which confers a longer biodegradation time. The surfaces of both types of microparticles were functionalized by plasma polymerization with allylamine to increase hydrophilicity and promote cell attachment. HF-hMSCs attached to and spread along the surface of both forms of PLGA microparticle. The osteogenic response of HF-hMSCs was enhanced when cultured with PLGA compared with control cultures differentiated on tissue culture plastic and this was independent of the type of polymer used. We have demonstrated that surface engineered PLGA microparticles are an appropriate biomaterial for combining with HF-hMSCs and the selection of PLGA is relevant only when considering the biodegradation time for each biomedical application.

Musculoskeletal aspiration procedures

With advances in imaging technology, there has been a significant increase in the number and range of interventional musculoskeletal image-guided procedures. One of the most commonly performed image-guided musculoskeletal interventions is the diagnostic and therapeutic percutaneous aspiration and drainage of multiple types of intra-articular, juxta-articular, and intramuscular pathologic fluid collections. These procedures may be performed under fluoroscopic, ultrasound, computed tomography, or even magnetic resonance guidance depending on the location to be accessed, type of pathology, patient characteristics, and operator preference. Musculoskeletal image-guided aspiration and drainage procedures are minimally invasive and generally very safe while offering valuable diagnostic information as well as therapeutic benefit. This article focuses on the appropriate indications, contraindications, and general technique for accessing the major joints via imaging guidance. For each joint, we discuss pertinent anatomy, appropriate imaging modalities, and preferred approaches to gaining intra-articular access. Additionally, the article discusses some of the more frequently encountered juxta-articular and intramuscular fluid collections that can be accessed and aspirated via percutaneous intervention, with mention of the importance of recognizing extremity sarcomas that can mimic these benign collections.

Laser Wavelength Dependence of Background Fluorescence in Raman Spectroscopic Analysis of Synovial Fluid from Symptomatic Joints

Gout is a disease process where the nucleation and growth of crystals in the synovial fluid of joints elicit painful arthritis-like symptoms. Raman spectroscopy is evolving as a potential diagnostic tool in identifying such crystals; however, attainment of sufficient Raman signal while overcoming the background fluorescence remains as a major challenge. The current study focused on assessing whether excitation in 532-700 nm range will provide greater signal intensity than the standard 785 nm while not being impeded by background fluorescence. We characterized the fluorescence spectra, absorption spectra and Raman spectra of synovial fluid from patients who presented "gout-like symptoms" (symptomatic) and controls (asymptomatic). A digestion and filtration method was developed to isolate crystals from synovial fluid while reducing the organic burden. Spectral profile and photobleaching dynamics during Raman spectroscopy were observed under an excitation wavelength range spanning 532 to 785 nm. Absorbance and fluorescence profiles indicated the digestion and filtration worked effectively to extract crystals from symptomatic synovial fluid without introducing additional fluorescence. Raman spectral analyses at 532 nm, 660 nm, 690 nm and 785 nm indicated that both asymptomatic and symptomatic samples had significant levels of fluorescence at excitation wavelengths below 700 nm, which either hindered the collection of Raman signal or necessitated prolonged durations of photobleaching. Raman-based diagnostics were more feasible at the longest excitation wavelength of 785 nm without employing photobleaching. This study further demonstrated that a near-infrared OEM based lower-cost Raman system at 785 nm excitation has sufficient sensitivity to identify crystals isolated from the synovial fluid. In conclusion, while lower excitation wavelengths provide greater signal, the fluorescence necessitates near-infrared wavelengths for Raman analysis of crystal species observed in synovial aspirates.

Usefulness and limitations of rapid urine dipstick testing for joint-fluid analysis. Prospective single-center study of 98 specimens

OBJECTIVE

To evaluate the diagnostic performance of rapid urine reagent strip testing of joint fluid in separating mechanical from inflammatory disease.

METHODS

In a prospective single-center 12-month study of joint fluid specimens, leukocyte esterase reagent strip testing (LERST) was compared to leukocyte counts used as the reference standard. Leukocyte counts greater than 2000/mm(3) were taken to indicate inflammation. Reproducibility of LERST was evaluated by testing 73 specimens twice and computing Cohen's kappa coefficient.

RESULTS

Ninety-eight joint fluid specimens (26 with mechanical and 72 with inflammatory characteristics) were evaluated. LERST had 79.2% sensitivity, 92.3% specificity, 96.6% positive predictive value, 61.5% negative predictive value, a positive likelihood ratio of 10.3, and a negative likelihood ratio of 0.23. The kappa coefficient was 0.70 (0.53-0.87). Two negative LERSTs a few minutes apart had 80% negative predictive value and a negative likelihood ratio of 0.08.

CONCLUSION

LERST of joint fluid is a rapid means of satisfactorily separating mechanical from inflammatory joint fluids.

Intra-articular glucocorticoids for acute gout

BACKGROUND

Although intra-articular glucocorticoids are a commonly used intervention in the treatment of acute gout, there is little evidence to support their safety and efficacy in this setting.

OBJECTIVES

To evaluate the safety and efficacy of intra-articular glucocorticoids in the treatment of acute gout.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE and Ovid EMBASE for studies to 16th October 2012. We also searched the 2010 to 2011 American College of Rheumatology (ACR) and European League against Rheumatism (EULAR) abstracts and performed a handsearch of the reference lists of articles considered for inclusion.

SELECTION CRITERIA

Studies were eligible for inclusion if they were randomised controlled trials (RCTs) or controlled clinical trials (CCTs) that used quasi-randomisation methods to allocate participants to treatment and compared intra-articular glucocorticoids to another therapy (active or placebo) in adults with acute gout. Outcomes selected for inclusion were pain, the proportion of participant withdrawals due to adverse events, inflammation, function, patient global assessment of treatment success, quality of life and proportion of particpants with serious adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies for inclusion and planned to extract the data and perform a risk of bias assessment.

MAIN RESULTS

No trials were identified that evaluated the efficacy and safety of intra-articular glucocorticoids for acute gout.

AUTHORS' CONCLUSIONS

There is presently no evidence from randomised trials to support the use of intra-articular glucocorticoid treatment in acute gout. Evidence suggests intra-articular glucocorticoids may be a safe and effective treatment in osteoarthritis and rheumatoid arthritis. These results may be generalisable to people with acute gout, and the treatment may be especially useful in people when non-steroidal anti-inflammatory drugs or colchicine are contraindicated.

Osteopontin level in synovial fluid is associated with the severity of joint pain and cartilage degradation after anterior cruciate ligament rupture

Objective

To explore the molecular function of Osteopontin (OPN) in the pathogenesis of human OA, we compared the expression levels of OPN in synovial fluid with clinical parameters such as arthroscopic observation of cartilage damage and joint pain after joint injury.

Methods

Synovial fluid was obtained from patients who underwent anterior cruciate ligament (ACL) reconstruction surgery from 2009 through 2011 in our university hospital. The amounts of intact OPN (OPN Full) and it’s N-terminal fragment (OPN N-half) in synovial fluid from each patient were quantified by ELISA and compared with clinical parameters such as severity of articular cartilage damage (TMDU cartilage score) and severity of joint pain (Visual Analogue Scale and Lysholm score).

Results

Within a month after ACL rupture, both OPN Full and N-half levels in patient synovial fluid were positively correlated with the severity of joint pain. In contrast, patients with ACL injuries greater than one month ago felt less pain if they had higher amounts of OPN N-half in synovial fluid. OPN Full levels were positively correlated with articular cartilage damage in lateral tibial plateau.

Conclusion

Our data suggest that OPN Full and N-half have distinct functions in articular cartilage homeostasis and in human joint pain.

Comparison of sonographically guided intra-articular injections at 3 different sites of the knee

OBJECTIVES

Sonographically guided injections show more accuracy than blind injections, but there are no reports comparing sonographically guided intra-articular injection approaches. This study examined the accuracy of sonographically guided intra-articular injections at 3 different sites of the knee using medial, midlateral, and superolateral portals.

METHODS

Sonographically guided intra-articular injections and radiology evaluations were performed on 126 knees with osteoarthritis (Kellgren-Lawrence grade 2 or 3). Six milliliters of mixed material containing 1% lidocaine (1 mL), 20 mg of triamcinolone (1 mL), and a nonionic contrast agent (4 mL) was injected into the intra-articular space of the knee through the medial, midlateral, and superolateral portals. After the sonographically guided intra-articular injection into the knee joint, a radiographic image was taken to determine whether the injected material had reached the intra-articular space or infiltrated into the soft tissue.

RESULTS

Sonographically guided intra-articular injections in the midlateral portal (95%; P < .05) and superolateral portal (100%; P < .05) showed significantly higher accuracy than injections in the medial portal (75%).

CONCLUSIONS

Sonographically guided intra-articular injections in the midlateral or superolateral portal may increase the accuracy of knee joint injections.

[Musculoskeletal puncture, injection and infiltration: swiss rheumatologists' point of view]

Arthrocentesis, injection and infiltration of joints and soft tissues belong to the basic procedures in rheumatology. The indications and the practical performance are based on experience and tradition. Nowadays, a crucial reappraisal and adaption of indications and technical aspects appear important in the light of new evidence and technical developments. The main indications for puncture remain the search of an infectious arthritis and reduction of intra-articular pressure due to effusion. Good indications for the injection of glucocorticoids are inflammation in sterile joints and activated osteoarthritis. The local infiltration with corticosteroids in mechanically induced enthesopathies at the lateral epicondyle of the humerus or at the plantar fascia have to be questioned in the light of recent publications which show that this common practice is associated with a poorer outcome than without injection.

Synovial fluid analysis for crystals

PURPOSE OF REVIEW

Describe why this review is timely and relevant. Identifying monosodium urate (MSU) and calcium pyrophosphate dehydrate (CPPD) crystals allows a quick and definitive diagnosis of both gout and CPPD arthritis, and remains the accepted gold standard. These diseases are still often diagnosed on inaccurate clinical grounds. Crystal identification has received little critical attention since its introduction, and it appears necessary to review the technique paying special attention to the possible reasons which deter clinicians.

RECENT FINDINGS

Describe the main themes in the literature covered by the article. Synovial fluid analysis for crystals is a simple procedure allowing immediate and definite diagnosis of gout and CPPD arthritis when clinics are fitted with a proper microscope and the rheumatologists appropriately trained. This review also illustrates how crystal analysis in synovial fluid can be initially approached with both the widely available ordinary light microscope and a simple polarized one and with good results.

SUMMARY

This study describes the implications of the findings for clinical practice or research. We hope that those not performing synovial fluid analysis will be stimulated to acquire or perfect the technique and obtain a compensated polarized microscope to comply with current standards.

Pain images: hip pain--wrong diagnosis, wrong operation

OBJECTIVE

The clinical presentation of retroperitoneal schwannoma with neuropathic pain and its subsequent management is presented.

DESIGN AND SETTING

This is a case report of a 67-year-old woman who developed left hip pain radiating into the postero-lateral portion of her left thigh and extending to the knee.

INTERVENTION

The patient underwent a left hip replacement for suspected pain from osteoarthritis of the hip joint.

OUTCOME MEASURE

The location of her pain was unchanged from the initial presentation, and more extensive investigations were carried out.

RESULT

The pain was found to be neuropathic in nature caused by a 54 mm retroperitoneal schwannoma.

CONCLUSION

Our case demonstrates the principle that unless the diagnosis is very clear (based on history, examination and diagnostic local anaesthetic injection, and confirmed by special investigations), surgery should not be considered. Where doubt exists, further assessment and investigation is required.